Heat transfer surface



March 1942' w. A. SPOFFORD 2,277,462

HEAT TRANSFER SURFACE Filed Dec. 22, 1939 Inven 1 Warren -SP by WW is A Q Patented Mar. 24, 1942 near raansrsa summon Warren a. s'noirord} Glen Ridge, N. 1., assignor to General Electric Company, a corporation of New York Application December 2, fish Serial No. 310,8l1

' 3 Claims. (01. ass-:02)

My invention relates to heat transfer surfaces and more particularly to a heat transfer element of the type having a plurality of heat exchange surfaces in the form of loops such as a coil of spirally wound heat conductive material secured to a cooling conduit.

When an extended heat transfer surface of the above type is applied to air conditioning equipment in which air is both cooled and dehumidiiied, it has been found that under some conditions condensed moisture forms on the loops in large drops and is blown off into the air stream When this con-- at relatively low air velocities. densed moisture blows into the air stream, it is necessary to provide some means for extracting this moisture from the air stream either by some type of water eliminator or by a drain pan extended far enough to collect all the water before it strikes a surface where it may be drained from the conditioner in such a way as to cause damage. Extracting means of this type are comparatively expensive.

Accordingly, it is an object of my invention to provide simple and improved means for collecting condensed moisture from the loops of such a type of heat exchange element before such moisture can be carried oil into the air stream.

Another object of my invention is to provide a continuous surface in the above described type of heat transfer surface on 'which condensed moisture may be collected and drawn to a point where it can be removed.

Further objects and advantages of my invention will become apparent as the following de-' scription proceeds and the features of novelty which characterize my invention will be pointedv out with particularity in the claims annexed to and forming a part of thisspeciflcation. For a better understanding of my invention reference may be had to the accompanying drawing in which Fig. 1 is an end view of a section of a cooling tube on which a heat transfer surface embodying the principles of my invention is ar ranged; Fig.2 is a side view, partly in section, of the heat transfer element illustrated in Fig. 1; and Fig. 3 is an enlarged partial view of a modiiication of the heat transfer surface illustrated in Figs. 1 and 2.

In Figs. 1 and 2 I have illustrated one embodiment of myinvention. There is shown a j cooling conduit or tube In having a heat transfer surface comprising a coil l I of spirally wound heat conductive material, such as copper wire, for example, wound on the tube ill and suitably 5 loops of the coil ll.

soldering. a drainage manner :2 is provided adjacent the loops of the coil II at the tips or outer periphery of the loops in order to collect any moisture which may be condensed on the The drainage member I2 illustrated in Figs. 1 and 2 comprises a wire threaded axially through the hollow ribbon or loops of the spirally wound wire coil II in such a way that it follows the outer periphery of the loops as illustrated thereby-providing a connection between the tips of the wire loops. I

Any drop of water forming on the wire loops will wet the surface of the connecting or drainage member I! and drain to the lowermost point .ll! of the heat transfer surface ll before falling off. The drainage member or connecting wire I!- mayor may not be mechanically secured at the outer periphery of the loops'of the coil H. In order to effect drainage of moisture it is necessary only that the drainage member I! be closely adjacent whereby it is sumcicntly close to the loops of the coil If so that a drop ofv moisture when forming will contact the drainage member I! before becoming of sufficient size to be blown off into the air stream. The collected moisture may be removed in any desired manner as by r permitting the moisture to drop onto the surfaces below or into a drain pan, not shown.

While the drainage member I! in the form of a wire is a simple means of providing for a continuous surface for the drainage or moisture, other methods of connecting the loops at the outer edge or periphery will occur to those skilledintheart. llbrexamplaawiresuchas illustratedinl 'lgaland2maybeadjacent the outer periphery of the loops of the cell It oneithertheinsideprthe outsideof the loops. In Fig. 3 I have shown a modification of my invention in which the drainagesurface at the outer. periphery of the coil II is provided by twisting the outer portion of the loops of the coil ,ll so as to form a continuous engagement between adjacent loops as indicated by the numeral II, for the drainage of moisture, although the twisted loops need not actually touch, if desired.

Othermodiflcationswilloccurtothoseskilled in the art. For example, my invention is applie cable to heat exchange members inwhich the loops have a substantially u-shaped configuration,.the arms of theUs being secured to the secured thereto in any desiredmanner as by be limited to the particular construction shown and described and I intend in the appended claims to cover all modifications within the spirit and scope or my invention.

What I claim as new and desire to secure by Letters Patent 01 the United States is:

1. In a heat transmitting element of the type comprising a conduit having secured thereto a plurality of loops 0! heat conductive material, substantially continuous means connecting ad- Jacent loops at substantially the outer periphery thereof for draining condensed moisture therefrom.

2. In a heat transmitting element 01 the type comprising a conduit having secured thereto a plurality of loops of heat conductive material, means for collecting. condensed moisture from said loops, said means comprising a wire extending through said loops and disposed sufiiciently close to the outer periphery of said loops to receive from said loops and to drain away therefrom any moisture condensing thereon.

3. In a heat transmitting element of the type comprising a conduit having secured thereto a spirally wound element comprising a plurality of loops of heat conductive material, means for collecting condensed moisture from said loops, said means comprising a wire extending axially through said loops and being disposed in engagement with said loops at the outer periphery thereof.

WARREN A. SPOFFORD. 

